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EN
As an intense tropical cyclone (TC) formed over the Bay of Bengal (BoB) in May 2023, Cyclone Mocha provides a significant opportunity to examine upper ocean responses to cyclonic forcing. Here, a spatio-temporal analysis has been done for cyclone induced Cold wake and sea surface height (SSH) changes through high-resolution daily satellite datasets combined with cloud computing through Google Earth Engine (GEE) and statistical analysis supported by Python-based processing. Buffering a spatial extent of 300 km along the cyclone track, the pre-cyclone period of 15 days was taken as the baseline for examination, 15th April’23–1st May’23, with a broader examination attempted from 15th April to 31st May’ 2023. Results indicated a strong cold wake occurring along Mocha’s track with sea surface temperature (SST) falling by around 2°C. Sea Surface Height Anomaly SSHA exhibited a moderate positive relationship with SST and a weaker recovery. The statistical interpretation from the results of Pearson’s correlation, Linear Trends and Causality (Granger) indicated a specific impact of the cyclone on SST and SSHA. The results validated cyclone-ocean interactions with strong indications of spatial and temporal alignment of regional dynamics, wind, SST and SSH. It also highlighted the strength of cloud computing and satellite outputs for ocean monitoring, forecasting, re-analysis, and resilience.
2
Content available Nowe rozdanie dla chemii w europejskich regulacjach
PL
Głosy decydentów w UE wskazują na to, że rok 2025 r. powinien przynieść strategiczne zmiany regulacyjne dla branży chemicznej, przynajmniej w formie strategii i projektów aktów prawnych. Będą się one ogniskować wokół kilku obszarów – warto śledzić tu działania związane z „Clean Industrial Deal” oraz „Chemicals Industry Package”.
3
Content available Mercury - the element that changed the world
EN
Mercury is a bright silver liquid with an exceptionally high density of 13.6 g·cm–3. It has a high surface tension, causing it to form bright shiny globules that roll freely on smooth surfaces. For this reason, it is sometimes called quicksilver. Not surprisingly, mercury has been the focus of insatiable curiosity since the earliest of times, a curiosity that has led to the use of mercury and its compounds in a vast range of applications in the fields of medicine, chemistry, physics and technology. Mercury has played a significant role in philosophical speculations about the nature of metals, and in scientific research. This has led to some remarkable results, from which we benefit on an everyday basis. The purpose of this article is to outline three major scientific discoveries, made during the past four centuries, which exploited the unique properties of mercury. The discoveries are associated with the names of five outstanding scientists - Torricelli, Priestley, Scheele, Lavoisier and Faraday. Using these discoveries as examples, it will be shown that mercury was the key player in the formation of today’s technological world.
4
Content available Maria Skłodowska-Curie i nagrody Nobla
EN
Marie Skłodowska-Curie is the only woman awarded the Nobel Prize twice: in physics in 1903 and in chemistry in 1911. She is also the only person to have received these awards in two different scientific disciplines. It is worth noting, however, that she almost did not receive any of them. In 1903, only Pierre Curie and Antoine Becquerel were nominated for the Nobel Prize. It was claimed that Marie Skłodowska-Curie was only her husbandʼs assistant. Thanks to the intervention of Pierre Curie, Marie was also appreciated. In 1911, Madame Curie was nominated for the Nobel Prize in Chemistry, but after French newspapers revealed her affair with Paul Langevin, some Swedish scientists demanded that she resign from receiving the prize. Strength of character, courage and independence made Marie Skłodowska-Curie not give in to attacks from public opinion and lies, and she received both Nobel Prizes with dignity, thus creating her legend.
EN
The influence of laboratory wastewater properties on heavy metals treatment efficiency by the chemical precipitation included aluminium sulphate (Al2(SO4)3) and poly aluminium chloride (PAC) using a stepwise multiple regression method. The laboratory wastewater properties showed high acidity approximately 0.75 and a highly turbid approximately 667.41 NTU that TSS (705.48 mg/L), COD (480.00 mg/L) and heavy metals such as Zn did not exceed the standards while Cu, Mn and Cr have levels exceeded the standards. Aluminium sulphate Al2(SO4)3) coagulant has treatment efficiency for reducing heavy metals at a pH of 9.00 to 73.62%, 99.94%, 98.43%, 68.76% and 99.25% for various heavy metals (Cu, Fe, Mn, Zn and Cr) respectively with original laboratory wastewater properties that parameters of laboratory wastewater include TSS, BOD, and pH having the highest influence on heavy metals treatment efficiency. The parameters of laboratory wastewater having the highest influence on heavy metals treatment efficiency when using poly aluminium chloride (PAC) were pH, COD, DO, and BOD when at a pH of 9.00 has treatment efficiency for reducing heavy metals to 73.67%, 99.94%, 98.45%, 69.76%, and 99.26% for various heavy metals (Cu, Fe, Mn, Zn, and Cr) respectively.
6
Content available remote XV Sesja Magistrantów i Doktorantów Łódzkiego Środowiska Chemików
7
Content available The extraordinary world of sulphur. Part 2*
EN
Sulphur is a highly reactive element, and is therefore able to enter into a wide variety of chemical combinations, resulting in the formation of compounds of widely differing properties. Reactions involving sulphur, and the compounds which they produce, have stimulated and inspired people throughout the ages. Sulphur has always been associated with volcanoes, fires and smells. However, its story goes much further; sulphur is present in thousands of products of the chemical industry, which are in everyday use. These include car batteries, tyres, matches, paints, paper, textiles, food, detergents and pharmaceuticals. In Part 1 of this essay, the evolution of the role of sulphur in the history of mankind has been explained, through the lenses of etymology, geology, literature, art and chemistry. In Part 2, the role of sulphur in biochemistry and chemical technology is reviewed. In presenting these facets of the world of sulphur, a case is established, to show that sulphur is one of the most useful and interesting substances known to Man.
EN
Chemistry plays a crucial role in everyday life, particularly in the kitchen, where its principles can enhance problem-solving skills and informed decision-making. This study aims to evaluate high school students’ understanding of applied chemistry in culinary contexts. A questionnaire was administered to 76 students, revealing that 42.6 % provided correct answers regarding the application of chemistry in the kitchen. The methodology involved analysing students’ responses to assess their awareness and appreciation of chemistry’s practical value. The findings suggest that promoting the application of chemistry principles not only fosters responsible citizenship but also optimises daily life benefits. Future research should explore effective strategies to enhance students’ engagement with chemistry in real-world contexts.
EN
Algeria has important phosphate reserves (2 billion tons) located in the east of the country at Djebel Onk. This mining district is located in the northwestern part of the Algerian Sahara near the Algerian-Tunisian border. The granulo-chemical and XRD analytical results confirm the phosphate depletion of Bled El Hadba layer and their enrichment in carbonate and dolomite, in comparison with the layer of Kef Essennoun. Phosphorite particles are heterogeneously grained. Although the two deposits are relatively close to each other, they show different mineralogical and chemical characteristics, which may cause the use of different mining exploitation methods.
PL
Algieria posiada ważne rezerwy fosforanów (2 miliardy ton) zlokalizowane na wschodzie kraju w Djebel Onk. Ten obszar górniczy znajduje się w północno-zachodniej części algierskiej Sahary, w pobliżu granicy algiersko-tunezyjskiej. Wyniki analiz granulochemicznych i XRD potwierdzają zubożenie fosforanów w warstwie Bled El Hadba i ich wzbogacenie w węglan i dolomit, w porównaniu z warstwą Kef Essennoun. Cząstki fosforytu są niejednorodnie ziarniste. Chociaż oba złoża znajdują się stosunkowo blisko siebie, wykazują różne właściwości mineralogiczne i chemiczne, co może powodować stosowanie różnych metod eksploatacji górniczej.
11
Content available The extraordinary world of Sulphur. Part 1
EN
Sulphur is a highly reactive element, and is therefore able to enter into a great variety of chemical combinations, resulting in the formation of compounds of widely differing properties. Reactions involving sulphur, and the compounds which they produce, have stimulated and inspired people throughout the ages. Sulphur has always been associated with volcanoes, fires and smells. However, its story goes much further. Sulphur is present in thousands of products of the chemical industry, which are in everyday use. These include car batteries, car tyres, matches, paints, paper, textiles, food, detergents and pharmaceuticals. In part 1 of this essay, the evolution of the role of sulphur in the history of mankind is explained, through the eyes of etymology, geology, literature, art, and chemistry. In part 2 the role of sulphur in biochemistry and chemical technology is reviewed. In so doing, a case is established, to show that sulphur is the most extraordinary substance known to Man.
12
Content available remote Bioaktywne substancje i właściwości farmakologiczne Fomitopsis betulina
PL
Związkami chemicznymi występującymi w pniarku brzozowym są: polisacharydy ((1→3)-α-D-glukany), kwasy poliporenowe, wolne cukry (mannitol, trehaloza), kwasy tłuszczowe (palmitynowy, stearynowy, oleinowy, linolowy), witaminy (kwas askorbowy), karotenoidy (b-karoten, likopen), α-, β-, ϒ-, δ-tokoferole, flawonoidy. Badania farmakologiczne różnych wyciągów z pniarka wykazały działanie: przeciwzapalne, przeciwbakteryjne, przeciwwirusowe (wyciągi: eterowy, octanu etylu), neuroprotekcyjne, immunomodulujące oraz przeciwnowotworowe (wyciągi: wodny i eterowy).
EN
The chemical compounds present in the birch stump are: polysaccharides ((1→3)-α- D-glucans), polyporenic acids, free sugars (mannitol, trehalose), fatty acids (palmitic, stearic, oleic, linoleic), vitamins (ascorbic acid ), carotenoids (b-carotene, lycopene), α-, β-, ϒ-, δ-tocopherols, flavonoids. Numerous studies have confirmed the biological activity. Pharmacological studies of various extracts from the plant have shown the following effects: anti-inflammatory, antibacterial, antiviral (extracts: ether, ethyl acetate), neuroprotective, immunomodulatory and anticancer (extracts: aqueous and ether). Pharmacological studies have shown the following effects: anti-inflammatory, antibacterial, antiviral, neuroprotective, immunomodulatory and anticancer.
13
Content available remote Wpływ związków chemicznych na zjawiska pogodowe
PL
Chemia jest szeroko obecna w zjawiskach pogodowych. Przykładem mogą być elektrony, które w górnych warstwach atmosfery zostają wzbudzone. Wówczas składniki atmosfery emitują różnokolorowe światła - jest to zjawisko zorzy. Zachodzi ono na skutek burz magnetycznych na Słońcu. Obserwowane przez nas barwy zorzy warunkują między innymi cząsteczki tlenu i azotu. Przykładem może być kolor czerwony oraz zielony określany nie tylko przez gazy, ale także wysokość na jakiej występuje zjawisko [1,2,3].
EN
Chemistry is widely present in weather phenomena. An example is electrons and atoms precipitating in the upper layers of the atmosphere, there they are excited. Then the components of the atmosphere emit different colored lights - this is the phenomenon of aurorae. It occurs due to magnetic storms on the Sun. The colors of the aurora we observe are conditioned, among other things, by oxygen and nitrogen molecules. As an example, red and green colors are determined not only by gases, but also by the altitude at which the phenomenon occurs [1,2,3].
PL
Jakość wody pitnej podlega bardzo restrykcyjnym regulacjom, a systemy wodne monitorowane są m.in. pod kątem mikroorganizmów istotnych dla zdrowia publicznego. W.systemach wodnych dominują heterotroficzne bakterie saprofityczne, oznaczane jako HPC (ang. Heterotropic Plate Count), jednak nie należy ich lekceważyć, ponieważ odgrywają one istotną rolę w tworzeniu biofilmów. Oprócz populacji bakteryjnych, często w systemach wodnych występują także grzyby z rodzajów: Penicillium, Phialophora, Cladosporium i Acremonium, drożdże, pierwotniaki (np. Bodo), wolne ameby (np. Hartmannela vermiformis, Vannella mira, Cochliopodium minutum), orzęski oraz glony. Wszystkie drobnoustroje mogą uczestniczyć w tworzeniu biofilmów na powierzchniach kontaktujących się z wodą. Biofilmy wpływają istotnie na mikrobiologiczną i organoleptyczną jakość wody pitnej a także na procesy korozyjne. Omówiono związki przyczynowe między tworzeniem biofilmów a pochodzeniem wody surowej, jej składem biologicznym i charakterystyką chemiczną.
EN
The quality of drinking water is subject to very strict regulations, and the water systems are regularly monitored, e.g. for microorganisms important to public health. Water systems are dominated by heterotrophic saprophytic bacteria, called HPC (Heterotropic Plate Count), but they should not be underestimated as they play an important role in the formation of biofilms. Apart from bacterial populations, fungi of the genera Penicillium, Phialophora, Cladosporium and Acremonium, yeasts, protozoa (e.g. Bodo), amoebas (e.g. Hartmannela vermiformis, Vannella mira, Cochliopodium minutum), ciliates and algae are also frequently present in water systems. All these microorganisms may participate in the formation of biofilms on surfaces in contact with water. Biofilms significantly affect the microbiological and organoleptic quality of drinking water as well as corrosive processes. The article discusses the causal relationships between biofilm formation and the origin of raw water, its biological composition and chemical characteristics.
15
Content available remote „Internacjonalizacja” polskiej nauki
EN
The membranes based on cellulose acetate (CA) were obtained by the method of phase inversion and used for removal of phenol (in concentrations of 15 and 25 mg/L) from liquid phase. To differentiate the hydrophilic properties of the membrane surfaces, different amounts of cellulose acetate (14 and 18 wt. %) and polyvinylpyrrolidone as a pore-generating agent (PVP, 1, 2, 3 or 4 wt. %) were used. The membranes were characterised by determination of their porosity, equilibrium water content, wetting angle and content of surface oxygen functional groups. After the application of membranes to phenol removal, the following parameters characterising the process were determined: permeability, membrane resistance, coke resistances, pore resistances, total filtration resistance and flux recovery ratio. The membranes were found to show higher effectiveness in phenol removal from a solution of the initial concentration 15 mg/L, and more effective were the membranes with higher contents of cellulose acetate. On the surface of the membranes the oxygen functional groups of acidic nature are dominant, both before and after filtration. The membranes of higher contents of cellulose acetate show higher resistances.
EN
Induction of the orthogonal smectic a phase occurs in mixtures of nematic compounds with positive and negative dielectric anisotropy. The aim of this work is to determine influence of a molecular structure of compounds on the induction strength of this phase. cyclohexyl tolanes with the terminal group -OCF₃, differing with a lateral substitution of a rigid core with fluorine atoms, were mixed with tolanes with two fluorine atoms in a lateral position and different lengths of a terminal alkoxy chain. Based on phase diagrams, obtained with the use of a polarising optical microscope, the influence of a structure of both types of compounds on the induction of the SmA phase is presented. Both, an increase in a number of fluorine atoms in a rigid core and a decrease in an alkoxy chain length cause a decrease in the strength of the SmA phase induction in the investigated systems.
PL
W mieszaninach związków ciekłokrystalicznych o dodatniej i ujemnej anizotropii dielektrycznej zaobserwowano indukcję fazy smektycznej A. celem pracy jest określenie wpływu struktury związków na temperaturowo-stężeniowy zakres występowania tej fazy. Cykloheksylotolany z terminalną grupą - OCF₃ różniące się lateralnym podstawieniem rdzenia atomami fluoru badano w układach z tolanami podstawionymi lateralnie dwoma atomami fluoru i różniącymi się długością terminalnego łańcucha alkoksylowego. na podstawie wykresów równowagi fazowej skonstruowanych z użyciem mikroskopu polaryzacyjnego określono wpływ obu grup związków na indukcję fazy smektycznej A. Zarówno zwiększenie liczby lateralnych atomów fluoru, jak i skrócenie łańcucha alkoksylowego powoduje zmniejszenie się indukcji fazy smektycznej A w badanych układach.
PL
Transformacja cyfrowa to proces nieunikniony, który nie jest już melodią przyszłości, a stał się teraźniejszością. Świadczy o tym mnogość inwestycji firm przemysłowych w innowacje, coraz większa gama dostępnych rozwiązań oraz narzędzi 4.0, a także fakt, że transformacja cyfrowa jest jednym z sześciu głównych celów zawartych w wytycznych Unii Europejskiej na lata 2019-2024. Wspieranie takiej transformacji nigdy wcześniej nie było tak wysoko sklasyfikowane na liście europejskich priorytetów.
EN
The springs of the Taoura region flow from a syncline shaped structure. All resources in the region were mobilized as a result of increased demand. However, the development of anthropic activities and population growth in the area pose risk for groundwater. Analytical results obtained from a series of samplings in November 2017–April 2018, express the quality of water suitable for the irrigation of agricultural land. The highest values are recorded in April 2018 at 20.5 to 21.6°C and pH of 8.0 to 8.2. The study recorded high electrical conductivity from 1390 to 1495 μS∙cm–1 and TDS from 1270 to 1500 mg∙dm–3 in November 2017, which shows important mineralization that characterizes spring water. Physical parameters were measured in situ using a HORIBA multi-parameter probe. Chemical analyses were carried out using NFT 90-005 titration, and nitrogen parameters by DIN 38405-D92 spectrophotometry. Maximum levels of nitrates and phosphates were recorded at 228 and 18.4 mg∙dm–3 respectively. The principal component analysis (PCA) showed a good correlation of the November 2017 period with mineralization parameters. Moreover, there is a strong correlation between the wet period and pollution factors. The two methods of analysis has allowed to distinguish three groups of geochemical water types: a bicarbonate calcium group typical for waters having transited in carbonate horizons. A second chloride calcium group shows basic exchange between water and clay levels, and the third chloride bicarbonate calcium group reveals an enrichment in calcium and chloride, which reflects water circulation with an exchange of the carbonated and evaporitic sedimentary rock matrix.
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